Break detection apparatus



Cd. 18, 1960 HIROMU OHNlSHl BREAK DETECTION APPARATUS 2 Sheds-Sheet 1Filed March 4, 1958 HIROMU OHNlSHl BREAK DETECTION APPARATUS Oct. 18,1960 2 Sheets-Sheet 2 Filed March 4, 1958 Unite States Patent Ofiice2,956,392 Patented Oct. 18, 1960 BREAK DETECTION APPARATUS HiromuOhnishi, 24 Shimizu-cho, Ashiya-shi, Hyogoken, Japan Filed Mar. 4, 1958,Ser. No. 719,115

2 Claims. (Cl. 57-81) This invention relates to automatic detectionapparatus, and more particularly to the detection of sliver breakage insliver processing apparatus.

It is an object of the invention to provide improved apparatus andmethods for the detection of sliver breakage.

It is another object of the invention to provide improved apparatus andmethods for detecting sliver breakage while distinguishing the same fromforeign objects which are capable of causing false indications.

It is another object of the invention to provide a simplified apparatusand method to perform a sliver breakage detecting function whileenabling the preservation of low costs, both as regards maintenance andproduction.

Still another object of the invention is to provide improved detectingapparatus which is foolproof insofar as detecting sliver breakage isconcerned.

In achieving the above and other of its objectives, the inventioncontemplates the provision of a device which applies a suction to asliver along the path of travel of the latter. This suction, when and ifthe sliver tends to break, urges the sliver in a predetermined directionalong which is positioned a mechanical feeler or displ aceable element,whose position is changed due to the movement thereagainst of thesliver. In further accordance with the invention, there is is providedan electrical circuit which responds to displacement of the displaceableelement for effecting a control function.

It will be appreciated that the application of suction as noted above toa sliver will tend to draw foreign objects, such as lint and insects, inthe above-noted direction. Ordinarily, this would cause the displaceableelement to give false indications and to control the electrical circuitat times other than when a sliver breaks. However, in further accordancewith the invention, means are provided for distinguishing between thebreaking of a sliver and the presence of foreign objects, said meansperforming its distinguishing function on the basis of the differentdurations of time by which the displaceable element is contacted by asliver or by one of said foreign objects.

In accordance with one of the features of the invention other than hasbeen indicated above, a particularly useful arrangement of displaceableelements is provided in which are provided a cam-type switch and anadjustable weight, as will hereinafter be described in greater detail.

In accordance with a further feature of the invention, special provisionis made for connecting the displaceable element to the electricalcircuit by means of lines which are well shielded.

As a further feature of the invention, the specific function ofdistinguishing between the durations of contact of different objectswith the displaceable element is performed by circuitry including delaydevices, such as thermistors.

Other objects and features of the invention, as well as advantagesthereof, will be apparent from the following detailed description of apreferred embodiment of the invention, as illustrated in theaccompanying drawing, in which:

Fig. 1 is a side view of apparatus comprising a sliver transportingdevice and a detector device provided in accordance with a preferredembodiment of the invention;

Fig. 2 illustrates in perspective and partially broken away a suctiontube, a displaceable element (in hidden view), and a portion of theassociated electrical circuit;

Fig. 3 is a front view of the apparatus of Fig. 2;

Fig. 4 is a side view of the apparatus of Fig. 3;

Fig. 5 is a top view of the apparatus of Figs. 3 and 4; and

Fig. 6 is a schematic diagram of the electrical circuit which theinvention preferably employs in connection with the displaceable elementin the above-indicated apparatus.

In Fig. 1 is generally indicated a sliver processing or transportingapparatus 10 comprising a frame 12 on which is supported a plurality ofrollers 14. The rollers 14 form a path for movement of a sliver 16 whichmay, for example, be frictionally driven by rollers 14.

Directly beneath the transport apparatus 10 is generally indicated adetecting device 18 provided in accordance with the invention. Theassociated electrical circuit is not shown in detail in this figure.

More particularly, detecting device 18 comprises a tube 20 having anozzle 22. To one end of the tube 18 is connected a vacuum pump 24 orsome similar type of device which is capable of causing a suction in thetube 20 and, hence, at the nozzle 22.

The nozzle 22 is positioned adjacent the path of travel of the sliver16. Hence, if the sliver 16 were to break as indicated at 26, the sliver16 would be drawn into the nozzle 22 and hence into the tube 20.

The detecting device 18 is provided with a detection element generallyindicated as element 28. As will be shown, detecting element 28 causessignals to be generated and transmitted to an electrical circuit bymeans of lines 30. It will be appreciated that the nozzle 22, aside fromdrawing in the sliver 16 when and if the same breaks, will also tend todraw into the tube 20 foreign objects, such as lint and insects. Thepresence of these foreign objects in the tube 2t), and more particularlyin the detecting element 28, will tend to cause a malfunc tion of thedevice. In accordance with the invention, provision is made to avoid thedeleterious effect of these foreign objects, despite their being drawninto the tube 20 via the nozzle 22.

Figs. 25 illustrate a section of the tube 20, which section supports andoperates in conjunction with the detecting element 28. These figureshave a similar content, excepting for the fact that a cover 34 (seeFigs. 3 and 4) attached to the detecting element 28 by means of a screwor bolt 36 is removed in Fig. 2.

In Figs. 25, the detecting element 28 is illustrated as provided with ahousing 38. Housing 38 is soldered, welded or otherwise connected withthe tube 20 and is operatively associated with the tube 20 adjacent aregion of the latter comprising a constriction 40 (Fig. 5). In thisconstricted portion is positioned a lever, feeler or finger 42. Lever 42is preferably positioned perpendicularly to the axis of tube 20.Moreover, it is supported on a shaft 44 upon which the lever 42 rotates,the shaft 44 being rotated when the lever 42 is pivoted. The lever 42constitutes the displaceable element in this embodiment of theinvention.

To one end of shaft 44 is affixed a weight 46 which is eccentricallydisposed with respect to said shaft. Accordingly, the weight 46 tends tomove in a predetermined direction under the influence of gravity andthus establish a normal position of repose for the lever 42.

Operatively associated with the weight 46 is an adjustment screw 48.This adjustment screw is urged into abutting relationship with thehousing or frame 38 so that the normal position of repose of lever 42can be adjusted.

Fixed to the housing 38 but electrically insulated therefrom is a switchconstituted in part by contacts t) and 52. Contact 50 is a fixedcontact, whereas contact 52 comprises a cantilever or leaf springportion adapted to be displaced against the contact 50. Thisdisplacement is controlled by means of a cam 54 which is affixed to theshaft 44 and rotates therewith. It follows as a consequence of theabove-indicated structure that the switch constituted by contacts 58 and52 is responsive to the movements of the lever or displaceable element42. From this it is clear that a movement of sliver 16 (Fig. 1) throughtube 2t? and against lever 42 in the direction ofarrow 56 in Fig. 2causes a displacement of lever 42 which, in turn, causes the contact 52to be moved against the contact 50.

The consequence of closing the switch comprising contacts 5t and 52 isnext seen with reference to Fig. 6, wherein these contacts areillustrated as incorporated in a circuit adapted for performing acontrol function. This circuit can be employed, for example, forcontrolling a utility device 56 which, for example, may be a motor or analarm.

The utility device 56 is provided with terminals 58 and 68, to which areconnected switches 6-2 and 64. Actually, switches 62 and 64 are parts ofelectromagnetic relays, as will be indicated hereinafter. it isimportant to note that switches 62 and 64 are arranged in parallel andare connected via terminal 66 to terminal 66, so that if either ofswitches 62 or 64 is closed the circuit of utility device 556 is closedand the latter is rendered operative. Similarly, it is important to notethat only when both of the switches 62 and 64 are opened is the circuitof utility device 56 opened, so that the latter is rendered inoperative.

It will be appreciated that the function hereinabove ascribed to thecircuit of utility device 56 may be varied considerably within the scopeof the invention. However, generally the changing of the condition ofthe circuit from open to closed state or vice versa will be consideredto the the function of generating a control signal or performing acontrol operation.

To render the control circuit of Fig. 6 operative, there is provided apower source (not shown) connected across terminals 68 and '76. Acrossthese terminals is connected the primary 72 of a transformer 74 havingtwo secondary windings 76 and 78. These secondary windings respectivelyconstitute power sources for their associated branches of the overallelectrical circuit.

Connected in series with secondary winding 66 is the winding 80 of arelay which controls the opening and closing of switch 62. Additionally,winding 80 controls the opening and closing of a switch 82 which may bean integral part of the relay. Normally, switch 62 is closed and switch82 is open. However, current flow through the winding 86 due to aclosing of contacts 58 and 52 causes switch 82 to be closed and switch62 to be opened.

As noted above, the opening of switch 62 does not open the circuitbetween terminals 58 and 60. This is due to the closed condition ofswitch 64. The closing of switch 32, however, permits current to flowthrough a relay winding 84, which has the effect of closing a normallyopen switch 86 which constitutes, with winding 84, a holding relay thecircuit of which is closed through a switch 88 independently of switch82 after the latter has initially enabled current to flow throughwinding 84. Current flow through winding 84 also operates to close aswitch 9% which may be an integral part of the relay constituted byswitch 86 and winding 84.

Switch 88 is an integral part of a relay comprising winding 92. Switch64 may be an integral part of a relay comprising winding 94. Windings 92and 94 are respectively connected in series with delay devices 96 and98, these devices being constituted by thermistors or other similarmechanisms capable of permitting operation after a predetermined ordeterminable time delay. Current flow through windings 92 and 94 and,therefore, through delay devices 96 and 98 is initiated upon a closingof switch 90, which occurs virtually simultaneously with the initiationof current flow through the winding 80.

Delay devices 96 and 98 have different operational delay periods. Thedelay device 96 has the longer of the time delay period, which may be,for example, about ten seconds. Delay device 98, which has the shorterof the two delay period, may have a delay period of, for example, twoseconds.

It is the function of delay device 98 to delay the effectiveness ofwinding 94, such that switch 64 is not opened until the expiration ofthe period of delay provided by device 98. This is very significant inthat, although current flow through winding will cause an immediateopening of switch 62, switch 64 will not be opened until a predeterminedperiod of time has elapsed following the initiation of current fiowthrough winding 80, this period being controlled by the characteristicof delay device 98. Accordingly, foreign objects, such as lint andflies, which tend only to cause an instantaneous displacement of lever42 (see, for example, Fig. 2), the displacement being of short duration,can only cause switch 62 to be opened, whereas switch 64 remains closed.In other words, lever 42 must be displaced to close the switchcomprising contacts 50 and 52 for a period of time which exceeds thecharacteristic time delay of device 98. This period of time is chosen tobe a period of time which distinguishes between displacement of lever 42by a broken sliver (i.e., a continuous displacement) and displacement ofthe lever 42 by foreign objects such as lint and insects.

The restoring of the electrical circuit to a condition whereat it isprepared to effect a detecting operation is provided by means of theswitch 88 operating in conjunction with winding 92 and delay device 96.Following a delay period determined by the characteristic of device 96,winding 92 is effective to open switch 88. The opening of switch 88,assuming that switch 82 has been previously opened, operates toterminate current flow through winding 84. This, in turn, opens switches86 and and, therefore, the circuit is primed for a further detectingoperation which can only be effected by current flow through winding 80and by the resulting closing of switch 82.

From the above, it is seen that switch 62 is opened immediately uponcurrent flow through winding 89, whereas switch 64 is opened only at theexpiration of a predetermined delay following current flow throughwinding 80, the delay being provided by delay device 98. Since both ofthese switches must be opened at the same time to open the circuit ofutility device 56, this opening will not be caused by instantaneousdisplacements of lever 42, which displacements are of short durationand, consequently, the apparatus is capable of distinguishing betweendisplacements caused by foreign objects such as have been enumeratedabove and by broken slivers.

Referring again to Fig. 2, it will be seen that lines 30 which connectcontacts 50 and 52 to the electrical circuit of Fig. 6 are physicallyaccommodated within a semicircular shield or casing 100 which is aflixedto the tube 20. This provides for safe, shielded connections as areprovided in accordance with a further feature of the invention.

The apparatus of the invention is simple yet efficient, and permits afoolproof detection of the breaking of one or more slivers in a sliverprocessing device.

There will now be obvious to those skilled in the art many modificationsand variations of the apparatus set 5 forth. These modifications andvariations will not, however, depart from the scope of the invention ifthey fall within the scope of the following claims.

What is claimed is:

1. Apparatus for detecting sliver breakage comprising tube having anopening adjacent said sliver, means coupled to said tube for producing avacuum in said tube thereby tending to suck the sliver into the tube,said sliver entering the tube only when broken, the vacuum in said tubetending to draw foreign objects into the same, a displaceable element insaid tube and displaceable for short periods of time by said foreignobjects and for longer periods of time by said sliver, processing meansadapted for processing said sliver, control means for rendering saidprocessing means effective and ineffective, first and second switcheseach connected to said control means and each of which must be opened tocause said control means to render said processing means ineffective,said first switch being controlled by said displaceable element, andmeans including a delay device for opening said second switch apredetermined period of time following the operation of the first saidswitch by said displaceable element.

2. Control apparatus responsive to a detector and capable ofdistinguishing between detector indications of different duration, saidcontrol apparatus comprising a circuit including two switches inparallel, said circuit being opened and therefore adapted to eflFect acontrol function only when both of said switches are open, a firstelectromagnetic means responsive to a detector indication of anyduration for opening one of said switches, and second electromagneticmeans responsive to a detector indication having a minimum predeterminedduration for opening the second of said switches, each of saidelectromagnetic means being responsive to the same detector indicationsso that both of said switches are opened only when a detector indicationexceeds in duration a predetermined minimum.

References Cited in the file of this patent UNITED STATES PATENTS2,271,178 Blom Jan. 27, 1942 2,383,838 Auble Aug. 28, 1945 2,500,343Carrette Mar. 14, 1950 2,704,430 Harris Mar. 22, 1955 2,812,632 TillettNov. 12, 1957 2,863,276 Bruening Dec. 9, 1958

